PCI: rcar: Try increasing PCIe link speed to 5 GT/s at boot (b3327f7f) · Commits · 戴 / test

drivers/pci/host/pcie-rcar.c

+66 −0

Original line number	Diff line number	Diff line
		@@ -84,8 +84,18 @@
		#define IDSETR1 0x011004
		#define TLCTLR 0x011048
		#define MACSR 0x011054
		#define SPCHGFIN (1 << 4)
		#define SPCHGFAIL (1 << 6)
		#define SPCHGSUC (1 << 7)
		#define LINK_SPEED (0xf << 16)
		#define LINK_SPEED_2_5GTS (1 << 16)
		#define LINK_SPEED_5_0GTS (2 << 16)
		#define MACCTLR 0x011058
		#define SPEED_CHANGE (1 << 24)
		#define SCRAMBLE_DISABLE (1 << 27)
		#define MACS2R 0x011078
		#define MACCGSPSETR 0x011084
		#define SPCNGRSN (1 << 31)

		/* R-Car H1 PHY */
		#define H1_PCIEPHYADRR 0x04000c
		@@ -385,11 +395,67 @@ static int rcar_pcie_setup(struct list_head resource, struct rcar_pcie pci)
		return 1;
		}

		static void rcar_pcie_force_speedup(struct rcar_pcie *pcie)
		{
		unsigned int timeout = 1000;
		u32 macsr;

		if ((rcar_pci_read_reg(pcie, MACS2R) & LINK_SPEED) != LINK_SPEED_5_0GTS)
		return;

		if (rcar_pci_read_reg(pcie, MACCTLR) & SPEED_CHANGE) {
		dev_err(pcie->dev, "Speed change already in progress\n");
		return;
		}

		macsr = rcar_pci_read_reg(pcie, MACSR);
		if ((macsr & LINK_SPEED) == LINK_SPEED_5_0GTS)
		goto done;

		/* Set target link speed to 5.0 GT/s */
		rcar_rmw32(pcie, EXPCAP(12), PCI_EXP_LNKSTA_CLS,
		PCI_EXP_LNKSTA_CLS_5_0GB);

		/* Set speed change reason as intentional factor */
		rcar_rmw32(pcie, MACCGSPSETR, SPCNGRSN, 0);

		/* Clear SPCHGFIN, SPCHGSUC, and SPCHGFAIL */
		if (macsr & (SPCHGFIN \| SPCHGSUC \| SPCHGFAIL))
		rcar_pci_write_reg(pcie, macsr, MACSR);

		/* Start link speed change */
		rcar_rmw32(pcie, MACCTLR, SPEED_CHANGE, SPEED_CHANGE);

		while (timeout--) {
		macsr = rcar_pci_read_reg(pcie, MACSR);
		if (macsr & SPCHGFIN) {
		/* Clear the interrupt bits */
		rcar_pci_write_reg(pcie, macsr, MACSR);

		if (macsr & SPCHGFAIL)
		dev_err(pcie->dev, "Speed change failed\n");

		goto done;
		}

		msleep(1);
		};

		dev_err(pcie->dev, "Speed change timed out\n");

		done:
		dev_info(pcie->dev, "Current link speed is %s GT/s\n",
		(macsr & LINK_SPEED) == LINK_SPEED_5_0GTS ? "5" : "2.5");
		}

		static int rcar_pcie_enable(struct rcar_pcie *pcie)
		{
		struct pci_bus bus, child;
		LIST_HEAD(res);

		/* Try setting 5 GT/s link speed */
		rcar_pcie_force_speedup(pcie);

		rcar_pcie_setup(&res, pcie);

		pci_add_flags(PCI_REASSIGN_ALL_RSRC \| PCI_REASSIGN_ALL_BUS);

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